This dot matrix is a great project for Arduino and dot matrix display newbie’s. Fun part is that this project doesn’t use a regular Arduino board, but instead it is assembled on a breadboard with ATmega168 with Arduino bootloader. Project uses a temperature compensated RTC clock with internal crystal chip DS3232 that gives great accuracy (±2ppm in normal conditions).

Clock is as it is without ability to set time – so there is place for improvement and design. This clock can be powered by two 10F 2.5V super caps that allow RTC clock running for several days.